Find out when she was last re-covered (this aircraft has a metal frame with a fabric skin) and see what structural inspections were done at the time; there's a good chance that some NDT inspections (x-ray and the like) would have been done, and the whole frame sand blasted and reprotected.
The Cub's a good, simple little aircraft and shouldn't give much trouble. You may also find some good info from the PFA ;
http://www.pfa.org.uk/